Portable electronic devices are typically powered by a battery. This allows the device to be used while not plugged into an electrical outlet. One example of a portable electronic device is a mobile device such as a smartphone or tablet computer. Mobile devices are becoming more and more ubiquitous. About 490 million mobile devices were sold in 2011. The number of mobile devices estimated to be in use by 2016 is 10 billion.
People rely on their mobile devices to make and receive phone calls, stay up-to-date on the latest news, take pictures, record video, watch movies, send and receive messages (e.g., email, or text messages), and much more. For example, many people use mobile application programs or apps for finding new places (e.g., mapping applications), social networking, entertainment (e.g., playing games), banking, shopping, keeping track of appointments (e.g., calendaring), and general productivity—just to name a few examples. The reliance on mobile devices is expected to grow exponentially.
These activities consume battery power. For example, battery power is consumed when acquiring location (e.g., GPS coordinates), running an application, making a phone call, sending a text message, and so forth. It can be very frustrating to want to use your mobile device only to find out that the battery is low or dead and you have no way of charging the device. For example, you may not be at home with your charger. In some cases, the loss of battery power can even be life-threatening if, for example, you were unable to make an emergency phone call or activate an emergency alert. Thus, there is a need to develop systems and techniques to intelligently manage mobile device battery use.